arch/arm64/kernel/smp.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
commit 83cfac95c018 ("genirq: Allow interrupts to be excluded from
/proc/interrupts") is to avoid IPIs appear twice in /proc/interrupts.
But the commit 331a1b3a836c ("arm64: smp: Add arch support for backtrace
using pseudo-NMI") and commit 2f5cd0c7ffde("arm64: kgdb: Implement
kgdb_roundup_cpus() to enable pseudo-NMI roundup") set CPU_BACKTRACE and
KGDB_ROUNDUP IPIs "IRQ_HIDDEN" flag but not show them in
arch_show_interrupts(), which cause the interrupt kstat_irqs accounting
is missing in display.
Before this patch, CPU_BACKTRACE and KGDB_ROUNDUP IPIs are missing:
/ # cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3
11: 466 600 309 332 GICv3 27 Level arch_timer
13: 24 0 0 0 GICv3 33 Level uart-pl011
15: 64 0 0 0 GICv3 78 Edge virtio0
16: 0 0 0 0 GICv3 79 Edge virtio1
17: 0 0 0 0 GICv3 34 Level rtc-pl031
18: 3 3 3 3 GICv3 23 Level arm-pmu
19: 0 0 0 0 9030000.pl061 3 Edge GPIO Key Poweroff
IPI0: 7 14 9 26 Rescheduling interrupts
IPI1: 354 93 233 255 Function call interrupts
IPI2: 0 0 0 0 CPU stop interrupts
IPI3: 0 0 0 0 CPU stop (for crash dump) interrupts
IPI4: 0 0 0 0 Timer broadcast interrupts
IPI5: 1 0 0 0 IRQ work interrupts
Err: 0
After this pacth, CPU_BACKTRACE and KGDB_ROUNDUP IPIs are displayed:
/ # cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3
11: 393 281 532 449 GICv3 27 Level arch_timer
13: 15 0 0 0 GICv3 33 Level uart-pl011
15: 64 0 0 0 GICv3 78 Edge virtio0
16: 0 0 0 0 GICv3 79 Edge virtio1
17: 0 0 0 0 GICv3 34 Level rtc-pl031
18: 2 2 2 2 GICv3 23 Level arm-pmu
19: 0 0 0 0 9030000.pl061 3 Edge GPIO Key Poweroff
IPI0: 11 19 4 23 Rescheduling interrupts
IPI1: 279 347 222 72 Function call interrupts
IPI2: 0 0 0 0 CPU stop interrupts
IPI3: 0 0 0 0 CPU stop (for crash dump) interrupts
IPI4: 0 0 0 0 Timer broadcast interrupts
IPI5: 1 0 0 1 IRQ work interrupts
IPI6: 0 0 0 0 CPU backtrace interrupts
IPI7: 0 0 0 0 KGDB roundup interrupts
Err: 0
Fixes: 331a1b3a836c ("arm64: smp: Add arch support for backtrace using pseudo-NMI")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Suggested-by: Doug Anderson <dianders@chromium.org>
---
v2:
- Report them in arch_show_interrupts().
- Add suggested-by.
- Update the commit message.
---
arch/arm64/kernel/smp.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 31c8b3094dd7..5de85dccc09c 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -767,13 +767,15 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
}
}
-static const char *ipi_types[NR_IPI] __tracepoint_string = {
+static const char *ipi_types[MAX_IPI] __tracepoint_string = {
[IPI_RESCHEDULE] = "Rescheduling interrupts",
[IPI_CALL_FUNC] = "Function call interrupts",
[IPI_CPU_STOP] = "CPU stop interrupts",
[IPI_CPU_CRASH_STOP] = "CPU stop (for crash dump) interrupts",
[IPI_TIMER] = "Timer broadcast interrupts",
[IPI_IRQ_WORK] = "IRQ work interrupts",
+ [IPI_CPU_BACKTRACE] = "CPU backtrace interrupts",
+ [IPI_KGDB_ROUNDUP] = "KGDB roundup interrupts",
};
static void smp_cross_call(const struct cpumask *target, unsigned int ipinr);
@@ -784,7 +786,7 @@ int arch_show_interrupts(struct seq_file *p, int prec)
{
unsigned int cpu, i;
- for (i = 0; i < NR_IPI; i++) {
+ for (i = 0; i < MAX_IPI; i++) {
seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,
prec >= 4 ? " " : "");
for_each_online_cpu(cpu)
--
2.34.1Hi,
On Wed, Jun 19, 2024 at 11:31 PM Jinjie Ruan <ruanjinjie@huawei.com> wrote:
>
> commit 83cfac95c018 ("genirq: Allow interrupts to be excluded from
> /proc/interrupts") is to avoid IPIs appear twice in /proc/interrupts.
> But the commit 331a1b3a836c ("arm64: smp: Add arch support for backtrace
> using pseudo-NMI") and commit 2f5cd0c7ffde("arm64: kgdb: Implement
> kgdb_roundup_cpus() to enable pseudo-NMI roundup") set CPU_BACKTRACE and
> KGDB_ROUNDUP IPIs "IRQ_HIDDEN" flag but not show them in
> arch_show_interrupts(), which cause the interrupt kstat_irqs accounting
> is missing in display.
>
> Before this patch, CPU_BACKTRACE and KGDB_ROUNDUP IPIs are missing:
> / # cat /proc/interrupts
> CPU0 CPU1 CPU2 CPU3
> 11: 466 600 309 332 GICv3 27 Level arch_timer
> 13: 24 0 0 0 GICv3 33 Level uart-pl011
> 15: 64 0 0 0 GICv3 78 Edge virtio0
> 16: 0 0 0 0 GICv3 79 Edge virtio1
> 17: 0 0 0 0 GICv3 34 Level rtc-pl031
> 18: 3 3 3 3 GICv3 23 Level arm-pmu
> 19: 0 0 0 0 9030000.pl061 3 Edge GPIO Key Poweroff
> IPI0: 7 14 9 26 Rescheduling interrupts
> IPI1: 354 93 233 255 Function call interrupts
> IPI2: 0 0 0 0 CPU stop interrupts
> IPI3: 0 0 0 0 CPU stop (for crash dump) interrupts
> IPI4: 0 0 0 0 Timer broadcast interrupts
> IPI5: 1 0 0 0 IRQ work interrupts
> Err: 0
>
> After this pacth, CPU_BACKTRACE and KGDB_ROUNDUP IPIs are displayed:
> / # cat /proc/interrupts
> CPU0 CPU1 CPU2 CPU3
> 11: 393 281 532 449 GICv3 27 Level arch_timer
> 13: 15 0 0 0 GICv3 33 Level uart-pl011
> 15: 64 0 0 0 GICv3 78 Edge virtio0
> 16: 0 0 0 0 GICv3 79 Edge virtio1
> 17: 0 0 0 0 GICv3 34 Level rtc-pl031
> 18: 2 2 2 2 GICv3 23 Level arm-pmu
> 19: 0 0 0 0 9030000.pl061 3 Edge GPIO Key Poweroff
> IPI0: 11 19 4 23 Rescheduling interrupts
> IPI1: 279 347 222 72 Function call interrupts
> IPI2: 0 0 0 0 CPU stop interrupts
> IPI3: 0 0 0 0 CPU stop (for crash dump) interrupts
> IPI4: 0 0 0 0 Timer broadcast interrupts
> IPI5: 1 0 0 1 IRQ work interrupts
> IPI6: 0 0 0 0 CPU backtrace interrupts
> IPI7: 0 0 0 0 KGDB roundup interrupts
> Err: 0
>
> Fixes: 331a1b3a836c ("arm64: smp: Add arch support for backtrace using pseudo-NMI")
> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
> Suggested-by: Doug Anderson <dianders@chromium.org>
> ---
> v2:
> - Report them in arch_show_interrupts().
> - Add suggested-by.
> - Update the commit message.
> ---
> arch/arm64/kernel/smp.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
Personally I don't find a ton of value in having the "CPU backtrace
interrupts" and "KGDB roundup interrupts" reported, but I agree that
if someone does find value in having them reported that this is the
best way. I guess that means a light:
Reviewed-by: Douglas Anderson <dianders@chromium.org>
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